摘要
以代表性蔬菜圆萝卜(Raphanus sativus L.)和小青菜(Brassica chinensis L.)为材料,分别添加0,2.5%,5%,10%和20%5个炭土干重比例的2种不同粒径生物炭到人工镉污染处理的土壤中进行盆栽实验。通过观察和分析植物生长发育状况及其根、茎、叶中重金属镉含量的变化,研究添加生物炭对促进蔬菜生长发育和抑制重金属污染及毒害的效果。结果表明:基质中添加生物炭可明显促进圆萝卜和小青菜的生长发育,2种蔬菜的株高和鲜重均显著增加(P<0.05)。由根冠比的变化发现,添加生物炭促进萝卜根的膨大作用大于其对茎叶的影响,而促进青菜叶的生长作用显著大于其对根的作用,这说明生物炭在一定程度上可促进蔬菜主要食用部分的产量。添加生物炭可使受镉污染土壤中生长的萝卜地下部分、青菜地上部分镉含量分别减少81.21%,83.04%。综合多项指标发现,针对实验所用2种蔬菜的最佳加炭量均为10%。因此,添加适当比例的生物炭可以明显减少蔬菜体内重金属镉的积累,使其达到可食用的标准。
To investigate the effects of biochar on plant growth and inhibition of heavy metal pollution,two representative vegetables（Raphanus sativus L.and Brassica chinensis L.）were used as plant materials in a pot experiment which 0,2.5%,5%,10%,and 20% of biochar-soil weight ratio gradients of two different diameter of biochars were added into soil polluted with artificial cadmium（Cd（NO3）2 ·4H2O）respectively.By observation and analysis of plant growth and development and heavy metal contents in leaves and roots,the effects of biochar on growth and development of plants and its inhibitory effect on toxicity of heavy metals were evaluated.The results showed that the addition of biochar into potting soil could significantly increase the growth of the two vegetables（P0.05）.According to the change of root shoot ratio,adding biochar in soil could improve R.sativus root biomass more obviously than increase the leaf biomass.However,the promotion of leaf growth was significantly greater than the root of B.chinensis.These results indicated that biochar could,to a certain extent,promote the production of major edible parts of tested vegetables.In addition,biochar in the soil reduced cadmium content of the underground parts of R.sativus and the aerial parts of B.chinensis by 81.21% and 83.04%,respectively.Taken several indicators into consideration,the optimum biochar to soil ratio was 10% for both R.sativus and B.chinensis.Therefore,adding an appropriate proportion of biochar into soil could significantly reduce accumulation of heavy metal cadmium in vegetables,and make them meet the food safety standard.
出处
《水土保持学报》
CSCD
北大核心
2013年第5期193-198,204,共7页
Journal of Soil and Water Conservation
基金
上海市绿化和市容管理局攻关项目(F112421)
湖南省自然科学省市联合基金项目(11JJ9007)
湖南省教育厅重点项目(10A031)
湖南省环保科技项目(湘财建指[2012]347号)
关键词
生物炭
重金属污染
植物生长发育
萝卜
小青菜
biochar
heavy metal pollution
plant growth and development
Raphanus sativus
Brassica chinensis
